Web guiding head



J. DUNGLER May 20, 1958 WEB GUIDING HEAD 5 Sheets-Sheet 1 Filed May 16, 1956 May 20, 1958 J. DUNGLER WEB GUIDING HEAD 3 Sheets-Sheet 2 Filed May 16, 1956 l'llllll-lll-ll May 20, 1958 J. DUNGLER WEB GUIDING HEAD 3 Sheets-Sheet 3 Filed May 16, 1956 WEB GUIDING HEAD Julien Dungler, Basel, Switzerland Application May 16, 1956, Serial. No. 585,231

7 Claims. (Cl. 2712.6)

The present invention relates to web guiding heads adapted to introduce fabrics at full width into finishing machines such as, for instance, tentering machines, padders, dyeing machines, drying machines, singeing machines, bleaching installations, folding machines, rolling machines, and so on.

Oscillatory introducing apparatus are already known which comprise two similar devices or heads mounted at the entrance to the machine, one for the right selvage, the other for the left selvedge, each head generally comprising two rolls between which the selvedge of the fabric to be guided travels, one of the rolls being fixed in the head and the other movable, the operation being such that, when the fabric departs laterally toward the axis of one selvedge guiding head, the latter has a progressively decreasing effect as the rolls of this head are brought nearer the horizontal, while the traction exerted by the opposite head brings the fabric back to normal position. v

The object of the present invention is to provide an apparatus of the aforesaid type which has a greater sensitivity and efiectiveness than those of the apparatus known up to now.

A web guiding head according to the invention is characterized in that it further comprises roll urging means carried by said frame for urging said rolls toward each other, frame urging means operativelyconnected to said frame for pivotally urging said frame to a position in which the axes of said rolls extend at right angles to the marginal portions of the'web, tensioning means carried by said frame and adapted to tilt said frame about said tilting axis against the action of said frame urging means as the marginal portion of the web departs laterally outwardly of its normal path of travel, and separating means operatively connected to said rolls and to said support and adapted to move said movable rolls away from each other as said frame is tilted toward the position in which the axes of said rolls extend at right angles to the marginal portion of the web.

Other objects and advantages of the invention will be apparent to those skilled .in the art, from a consideration of the following description of two specific embodiments of the invention, shown by way of examples, in the accompanying drawings, in which:

Fig. 1 is an elevational front view of an improved cloth guiding head.

Fig. 2 is a top view thereof.

Fig. 3 is an end view corresponding to Fig. 1, it being assumed that the counterweight is removed.

'Fig. 4 is a modification inwhich a restoring spring is substituted for the counterweight and a sheave mounted in place of the fork; and

- Figs. 5 and 6 are diagrams showing the apparatus in various steps of operations.

An introducing apparatus is composed of two symmet rical heads A and A (Figs. 5 and 6) respectively positioned on the right and on the left side of the entrance United States Patent 0 P 2,835,490 Patented May 20, 1958 t0 the machine receiving the web or fabric at full width, it being assumed that the apparatus is mounted on a web moving vertically and downwardly. Each head comprises (Figs. 1, 2 and 3) a support 1 by means of which the head is bolted onto the machine or on the device adapted to support it. A frame 2 is pivotally mounted on a shaft 3 rigid with the support 1. On the frame 2 is mounted a shaft 4 carrying a stationary roll 5. A movable roll- 6 is mounted on a shaft 7 rigid with a swinging arm 8 carried by a shaft 9 which is journalled in a sleeve 2a. The lower portion of the swinging arm 8 is formed with an extension carrying a stub shaft 10 on which is mounted a cam follower 11 which, accord ing to the inclination of the frame 2, is able to engage a cam 12 fixed on an arm 1a rigid with the support 1. The roll 6 is urged toward the roll 5 by a spring 13 secured, on one hand, to the free end of the shaft 7, and, on the other hand, to the frame 2 through the medium of a screw 14 provided with a thumb nut 15 adapted to ensure the accurate adjustment of the pressure exerted by the spring between the rolls 5 and 6. A device 16 secured to the frame 2, and on which the selvedge is tensioned, that is to say which obliges said selvedge to assume a more undulated form as it engages more deeply thereon, is constituted by a fork the branches of which are bent in such a manner that, in vertical projection, they diverge from their points of attachment.

At rest, the heads A and A assume an inclined position, as shown in Fig. 5, under the action of a counterweight 17 mounted on a. lever rigid with the frame 2. This disposition may be adopted for guiding a fabric moving in a vertical direction or in a direction much inclined to the horizontal. For guiding a web in a horizontal direction or in a direction only slightly inclined to the horizontal, the counterweight should be moved to another position or replaced by a spring 18 connecting an upper projection ofthe support 1 to the frame 2 (Fig. 4). At rest, the rolls of each head are maintained in their lower limit position under the effect of the counterweight 17, that is to say their angle to the horizontal is maximum (Fig. 5).

After having engaged the fabric into both heads A and A, the distance between the latter is being adjusted. When getting near the outer end of the rolls, the selvedge engages the fingers of the tensioning fork 16.

At this moment, the rolls leave their lower limit position and progressively tend toward the horizontal position as the penetration of the fabric into the fork increases.

Now, if it is assumed that the fabric moving downwardly departs away from its normal path toward the left (Fig. 6), the left selvedge then penetrates more deeply between the branches of the tensioning fork 16 of the head A. The tensioning effect increases to a great extent and augments the tilting movement of the support 2 on the shaft 3 and the head, therefore, reaches a position nearer the horizontal.

At this moment, the cam follower 11 engages the. inclined plane of the cam 12 and a short travel of the follower on the cam exerts upon the swinging arm 8 a force opposing the traction effect of the spring 12, which results in the roll 6 being moved away from the roll 5. The left selvedge engaged between these rolls is thus released and the transverse traction effect previously exerted by this head upon the fabric is now abolished. However, owing to the deviation of the fabric toward the left, the right head will have augmented its inclination with respect to the horizontal and exert its full transverse traction power for bringing the fabric back into its normal path, the left selvedge, therefore, will reassume its normal position and partially move out of the tensioning fork. Since the support 2 reassumes its normal inclination, the follower llclears' the"caim"12 and the roll 6 will again engage: the fabric under the action of the spring 13. Thepressure exerted by both rolls against the fabric, combined with the transverse traction due to the inclination of the rolls,willfmaketlrishead capable to act efficie'ntly in the opposite direction-should the fabric move out'of its normalpath towardthe right.

A similar operatio'n'is obtained when the 'co'imter weight is replaced by a restoring spring 18 and/or'the tensioning fork by a grooved wheel 19 (Fig. 4) or any other suitable means. In fact, assuming, as previously, a deviation of the fabric toward the left, thelcorresponding selvedge will penetrate between the'fianges'of the grooved wheel, and under its impulse thewheel will effect a rotational movement on its shaft 20. A cable 21 attached by one of its ends to this shaft and by its other end to the frame 2 will wind about this shaft and make the frame 2 tilt on the shaft 3, which will have for result to initiate the operation previously described. When the fabric again travels on its normal path, the wheel 19, under the action of the spring 18 (or of a counterweight), will start rotating in a direction opposite to that of the movement of the selvedge and the cable 21, now released, will enable the frame 2 to reassume' its normally inclined position. Of course, the embodiments hereinabove described and represented in the drawings are given only by way of non restrictive examples, and the form, nature, assembly and disposition of'their elements, may be modified in any suitable manner without the scope of the invention being departed thereby.

Thus, for example, the mechanism for moving the rolls away from each other and/or the means for tilting the frame may be replaced by an electro-magnetical or pneumatic device. In the place of the grooved wheel, a small rod with a surface preferably knurled and with a frusto-conical end may be provided. The cable may be replaced by a toothed rack, or any suitable device.

What I claim is:

1. A web guiding head comprising in combination: a support, a frame pivotally mounted on saidsup'port on a tilting axis positioned substantially at right angles to the plane of said web, a pair of rolls journalled in said frame on parallel axes at right angles to said'tilting axis and mounted for movement toward'and away from each other, roll urging means carried by said frame for urging said rolls toward each other, said rolls being so positioned in said frame that the web may travel between said rolls, frame urging means operatively connected to said frame for pivotally urging said frame to a position in which the axes of said rolls extend angularly with respect to the marginal portions of the web, tensioning means'carried bysaid'frame and adapted to'tilt'said frame about said tilting axis against the action of said frame urging means as the marginal portion of the web departs laterally outwardly of its normal path of travel, and separating means operatively connected to said rolls and to said support and adapted to move saidmovable rolls away from each other 'as said frame is tilted toward the position in which the axes of said rolls extend at right angles to the marginal portion of the web.

2. A web guiding-head according to claim 1, wherein one of said rolls is journaled on a shaft rigid on said frame while the other roll is journalled on a shaft carried by a swinging lever adapted to swing on said frame about an axis extending parallel with the axis of said other roller.

3. A web guiding head according to claim 2, wherein said separating means are constituted by a camming face fixed on said support and a cam follower rotatably mounted on said swinging lever and adapted to cooperate with said camming face.

4. A web guiding head according to claim 1, wherein said frame urging means are constituted by a counterweight fixed on said frame and so positioned thereon that said tilting axis is located between said counterweight'and said rolls.

5. A web guiding head according to claim 1, wherein said frame urging means are constituted by a spring operatively connected both to said frame and to said-support.

6. A web guiding head according to claim 1, wherein said tensioning means are constituted by a fork rigid on said frame and having diverging branches adapted to be frictionally engaged by said marginal portion of said web as the latter departs laterally outwardly of its normal path of travel.

7. A web guiding head according to claim 1, wherein said tensioning means are constituted by the combination of a grooved wheel rotatably mounted on said frame in the plane of said web and adapted to be frictionally engaged by the lateral edge of the latter when said web is departing laterally outwardly of its normal path of travel, and a flexible link one end of which is attached to said grooved wheel and the other end'is attache'd'to said frame.

References Cited in the file of this patent UNITED STATES PATENTS 

